Rumours that the company is planning to discontinue its tablet have surfaced before. In July, RIM denied it’s discontinuing the product line, and said it has plans for further rollouts of the device around the world.

The reports come as the BlackBerry maker confirmed Thursday that Tyler Lessard, vice-president of global alliances and developer relations, has resigned from the company. The company also confirmed the departure of Jeff McDowell, vice-president of platform marketing and alliances.

In all, at least five senior executives at RIM have announced their departure in recent months. Bloomberg News reports:

Mike Kirkup, senior director of developer relations, announced his departure in a blog post in August. Ryan Bidan, the product manager in charge of RIM’s PlayBook tablet computer, left for Samsung Electronics Co. in July. Brian Wallace left his job as head of digital marketing at RIM, to join Samsung in June. Chief Marketing Officer Keith Pardy gave his notice with the company in March.

According to CrackBerry, the departing execs were largely associated with BBOS, RIM’s traditional operating system, while their replacements are associated with QNX, the software company RIM bought in 2010, whose operating system will be used in upcoming generations of BlackBerrys.

As evidence, CrackBerry points to the appointment of Alec Saunders to vice president of developer relations. Saunders had once held the position of vice president of marketing at QNX.

RIM has had a historically bad year, releasing a series of disappointing earnings reports as the company saw its BlackBerry rapidly lose market share to the iPhone and Android phones. As of this week, Bloomberg reports the company’s shares were down 62 per cent for the year.